OK...you said offshore sailors so I will assume the questions do NOT pertain to Idaho!
1. It would catch a little wind but not much. Biggest danger is from waves and breaking seas and the forces exterted on the davit mounts.
2. The motor should never be left on. It is hung on the stern rail on a bracket.
3. Davits should NEVER be used at sea. The dinghy belongs on the foredeck tied down. Davits are used at anchor and on calm coastal sailing days.
A quality INFLATABLE dinghy will be well made by a recognized mfr. and use hypalon for resistance to the damage of the sun. Recognized quality brands include: Avon, Caribe, Zodiac, Achilles, Walker Bay, AB, and probably a few others I've failed to remember at the moment.
Beyond inflatable you also need to choose capacity, wood or aluminum floor, no floor, air floor or RIB and the size motor required for that dinghy and what you want to do with it.
Then there are hard dinghys, nesting dinghies and portaboats, kayaks etc. that serve as dinghies. I'll leave those to others as I am a confitmed RIB fan.
RIB= Rigid Inflatable Boat= fiberglass bottom and inflatable tubes.
They are much less tippy and hold more weight and stand up to groundings better especially in coral areas. They go fast too which is important when you travel long distances in them to fish or hit the reefs for some diving...or when there is a squall coming and you have just barely enough time to make it back to the boat!
The downside is that they are expensive and heavier than the pure inflatables and require enough room on deck to tore the rigid part and can't be rolled up an stashed for storage like other inflatables.
No longer posting. Reach me by PM!